API for conventional archive and executable file names.

Closes #33.

plugins/src/main/java/br/dev/pedrolamarao/gradle/metal/base/MetalArchiveTask.java

@@ -50,8 +50,8 @@ public Provider<RegularFile> getOutput ()
     {
         return getOutputDirectory().map(out -> {
             final var target = getTarget().get();
-            final var name = getProject().getName();
-            return out.file("%s/%s.lib".formatted(target,name));
+            final var file = getMetal().get().archiveFileName(target,getProject().getName());
+            return out.file("%s/%s".formatted(target,file));
         });
     }
 

plugins/src/main/java/br/dev/pedrolamarao/gradle/metal/base/MetalExtension.java

@@ -17,6 +17,8 @@
 @NonNullApi
 public abstract class MetalExtension implements ExtensionAware
 {
+    // properties
+
     /**
      * Metal service.
      *
@@ -46,7 +48,7 @@ public abstract class MetalExtension implements ExtensionAware
      */
     public Provider<String> getHostTarget ()
     {
-        return getMetalService().flatMap(MetalService::getHostTarget);
+        return getMetalService().map(MetalService::getHost);
     }
 
     /**
@@ -56,6 +58,30 @@ public Provider<String> getHostTarget ()
      */
     public abstract ListProperty<String> getLinkOptions ();
 
+    // methods
+
+    /**
+     * Formats an archive file name according to the host conventions.
+     *
+     * @param name  core name
+     * @return      file name
+     */
+    public Provider<String> archiveFileName (String name)
+    {
+        return getMetalService().map(it -> it.archiveFileName(name));
+    }
+
+    /**
+     * Formats an executable file name according to the host conventions.
+     *
+     * @param name  core name
+     * @return      file name
+     */
+    public Provider<String> executableFileName (String name)
+    {
+        return getMetalService().map(it -> it.executableFileName(name));
+    }
+
     /**
      * Locate tool.
      *

plugins/src/main/java/br/dev/pedrolamarao/gradle/metal/base/MetalLinkTask.java

@@ -56,8 +56,8 @@ public Provider<RegularFile> getOutput ()
     {
         return getOutputDirectory().map(out -> {
             final var target = getTarget().get();
-            final var name = getProject().getName();
-            return out.file("%s/%s.exe".formatted(target,name));
+            final var file = getMetal().get().executableFileName(target,getProject().getName());
+            return out.file("%s/%s".formatted(target,file));
         });
     }
 

plugins/src/main/java/br/dev/pedrolamarao/gradle/metal/base/MetalService.java

@@ -1,33 +1,47 @@
 package br.dev.pedrolamarao.gradle.metal.base;
 
+import org.gradle.api.GradleException;
 import org.gradle.api.provider.Provider;
 import org.gradle.api.provider.ProviderFactory;
 import org.gradle.api.services.BuildService;
 import org.gradle.api.services.BuildServiceParameters;
+import org.gradle.process.ExecOperations;
 
 import javax.inject.Inject;
-import java.io.File;
+import java.io.*;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.concurrent.atomic.AtomicReference;
 
 /**
  * Metal service.
  */
 public abstract class MetalService implements BuildService<BuildServiceParameters.None>
 {
-    private final Provider<String> hostTarget;
+    private final AtomicReference<String> hostTarget = new AtomicReference<>();
 
-    private final Provider<String> path;
+    private final String path;
 
     /**
      * Constructor.
      */
     @Inject
     public MetalService ()
     {
-        hostTarget = getProviders().of(MetalHostTargetSource.class, it -> {});
         path = getProviders().gradleProperty("metal.path")
-            .orElse(getProviders().environmentVariable("PATH"));
+            .orElse(getProviders().environmentVariable("PATH"))
+            .orElse("")
+            .get();
     }
 
+    /**
+     * Exec operations service.
+     *
+     * @return service
+     */
+    @Inject
+    protected abstract ExecOperations getExec ();
+
     /**
      * Provider factory service.
      *
@@ -39,11 +53,117 @@ public MetalService ()
     /**
      * Host target.
      *
-     * @return provider
+     * @return target name
+     */
+    public String getHost ()
+    {
+        final var cached = hostTarget.get();
+        if (cached != null) return cached;
+
+        final var buffer = new ByteArrayOutputStream();
+        getExec().exec(exec -> {
+            exec.executable( Metal.toExecutableFile(path,"clang") );
+            exec.args("-v");
+            exec.setErrorOutput(buffer);
+        });
+
+        String value = null;
+        try (var reader = new BufferedReader( new StringReader( buffer.toString() ) ) )
+        {
+            String line;
+            while ((line = reader.readLine()) != null) {
+                if (line.startsWith("Target")) {
+                    final var split = line.split(":");
+                    if (split.length != 2) continue;
+                    value = split[1].trim();
+                    break;
+                }
+            }
+        }
+        catch (IOException e) { throw new GradleException("failed parsing clang -v output", e); }
+
+        if (value != null) {
+            hostTarget.set(value);
+            return value;
+        }
+
+        throw new GradleException("failed to discover host target");
+    }
+
+    /**
+     * Formats an archive file name according to the host convention.
+     *
+     * @param name  core name
+     * @return      file name
+     */
+    public String archiveFileName (String name)
+    {
+        return archiveFileName(getHost(),name);
+    }
+
+    /**
+     * Formats an archive file name according to the target convention.
+     *
+     * @param target  target
+     * @param name    core name
+     * @return        file name
+     */
+    public String archiveFileName (String target, String name)
+    {
+        final var prefix = archiveFilePrefix(target);
+        final var suffix = archiveFileSuffix(target);
+        return "%s%s%s".formatted(prefix,name,suffix);
+    }
+
+    String archiveFilePrefix (String target)
+    {
+        final var parts = target.split("-");
+        if (contains(parts,"msvc")) return "";
+        else return "lib";
+    }
+
+    String archiveFileSuffix (String target)
+    {
+        final var parts = target.split("-");
+        if (contains(parts,"msvc")) return ".lib";
+        else return ".a";
+    }
+
+    /**
+     * Formats an executable file name according to the host convention.
+     *
+     * @param name  core name
+     * @return      file name
      */
-    public Provider<String> getHostTarget ()
+    public String executableFileName (String name)
     {
-        return hostTarget;
+        return executableFileName(getHost(),name);
+    }
+
+    /**
+     * Formats an executable file name according to the target convention.
+     *
+     * @param target  target
+     * @param name    core name
+     * @return        file name
+     */
+    public String executableFileName (String target, String name)
+    {
+        final var prefix = executableFilePrefix(target);
+        final var suffix = executableFileSuffix(target);
+        return "%s%s%s".formatted(prefix,name,suffix);
+    }
+
+    String executableFilePrefix (String target)
+    {
+        return "";
+    }
+
+    String executableFileSuffix (String target)
+    {
+        final var parts = target.split("-");
+        if (contains(parts,"windows")) return ".exe";
+        else return "";
     }
 
     /**
@@ -54,6 +174,24 @@ public Provider<String> getHostTarget ()
      */
     public Provider<File> locateTool (String name)
     {
-        return path.map(it -> Metal.toExecutableFile(it,name));
+        for (var item : path.split(File.pathSeparator))
+        {
+            final var directory = Paths.get(item);
+            if (! Files.isDirectory(directory)) continue;
+            final var file = directory.resolve(name);
+            if (Files.isExecutable(file)) return getProviders().provider(file::toFile);
+            final var file_exe = file.resolveSibling(name + ".exe");
+            if (Files.isExecutable(file_exe)) return getProviders().provider(file_exe::toFile);
+        }
+
+        throw new GradleException("executable file not found: " + name);
+    }
+
+    static <T> boolean contains (T[] array, T value)
+    {
+        for (T item : array)
+            if (item.equals(value))
+                return true;
+        return false;
     }
 }

plugins/src/main/java/br/dev/pedrolamarao/gradle/metal/base/MetalSourceTask.java

@@ -42,6 +42,6 @@ public abstract class MetalSourceTask extends SourceTask
      */
     protected MetalSourceTask ()
     {
-        getTarget().convention( getProviders().gradleProperty("metal.target").orElse( getMetal().flatMap(MetalService::getHostTarget) ) );
+        getTarget().convention( getProviders().gradleProperty("metal.target").orElse( getMetal().map(MetalService::getHost) ) );
     }
 }